Cannabis commercialisation not decriminalisation drives up usage, study finds

The commercial sale of cannabis, not its decriminalization, appears to be the primary driver of increased usage and associated mental health problems, according to a new international study. The review, which analyzed policy changes and their effects between 2000 and 2025, found a significant correlation between commercialization and rising numbers of cannabis users.

Researchers observed that in countries where cannabis is sold commercially, there is a notable increase in both the number of people consuming the drug and the rates of psychosis. This contrasts with regions where possession has been decriminalized or access is strictly regulated, which did not show similar upticks in usage.

The study's findings suggest that policy decisions surrounding cannabis sales have direct consequences on public health. The analysis considered changes in drug potency and the prevalence of mental health issues following the implementation of new regulations.

“

Decriminalising the possession of cannabis or strictly regulating access to the drug do not appear to drive up usage, but when the drug is sold commercially the number of users increases and more mental health problems are seen, a review has found.